Guiding assembly for dental restoration procedures

ABSTRACT

A dental guidance assembly that includes: (a) a rigid body comprising at least one tooth-shaped recess and a coupling structure; and (b) at least two dental bur guides that are each: structured to securely and removably couple to said coupling structure, and comprising an elongated slot having the following measurements: a length of 4 to 40 millimeters, a width of 1 to 4 millimeters, and a depth of 2 to 10 millimeters. The elongated slot extends along a portion of a circumference of a treated tooth, wherein the elongated slots of said at least two dental bur guides have complementary structures, such that, together, the elongated slots are configured to facilitate a limitation of the motion of a dental bur to: an entirety of the circumference of a treated tooth, and a depth suitable to form a shoulder on the treated tooth, for receiving a dental restoration.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/557,109 filed on Sep. 10, 2017, which is a National Phase Applicationof PCT PCT/IL2016/050260, which claims the benefit of priority of IsraelPatent Application No. 237637, filed Mar. 9, 2015, and Israel PatentApplication No. 242477, filed Nov. 5, 2015, both entitled “GUIDINGAPPARATUS FOR USE IN DENTAL RESTORATION PROCEDURES.” All applicationsare incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The invention relates to the field of dental guiding assemblies.

BACKGROUND

Dental procedures, such as dental crown procedures, dental capprocedures, dental implant procedures, and/or the like, may requirepreparing a tooth by reshaping the tooth surface. An x-ray image may betaken to check the roots of the tooth, and when a root canal is notneeded the tooth is reshaped. Support material may be used to fill upthe tooth surface to support the crown. Once the surface is reshaped, animpression of the reshaped tooth structure may be acquired for preparinga dental restoration. For example, the tooth impression is used to makea dental crown at a specialized laboratory, sent to the dentist a fewweeks later, and attached to the reshaped tooth during a second visit.

The tools that are used for reshaping are usually dental drills withdental burs attached to the drill for reshaping the tooth. The dentistchooses one of several available dental bur shapes, and files down thetreated tooth with the dental bur to prepare the surface to receive thecrown. The dental surgeon carefully moves the rotating dental bur acrossthe tooth surface to remove some of the tooth material and reshape thetooth. The reshaped tooth for receiving a crown should have enoughsurface to support the interior of the crown for good mechanicalsupport.

All crowns have a minimal thickness and may need some space to fit onthe treated tooth to ensure that the crown has the same size as theoriginal healthy tooth. The minimal thickness ensures the crown hasadequate mechanical strength, such as for example a thickness of one ortwo millimeters. For example, porcelain crowns require enough ceramicthickness to reduce translucency such as 1.5 millimeters thickness, andthus a treated tooth needs to be filed down by at least 1.5 millimeter.The tooth reshaping may further require a tapering, so that a dentalcrown may be easily attached to the tooth. Additionally, a margin mustbe taken into account when reshaping a tooth, such as a shoulder, achamfer, a bevel, and/or the like.

Similar procedures exist for dental overlays, dental ¾ crowns, dentalimplants, dental prostheses, prosthetic crown, and/or the like. As usedherein, the term dental restoration means any artificial material usedto restore a tooth structure, such as a dental crown, an inlay, anoverlay, a dental implant, and the like.

The foregoing examples of the related art and limitations relatedtherewith are intended to be illustrative and not exclusive. Otherlimitations of the related art will become apparent to those of skill inthe art upon a reading of the specification and a study of the figures.

SUMMARY

The following embodiments and aspects thereof are described andillustrated in conjunction with systems, tools and methods which aremeant to be exemplary and illustrative, not limiting in scope.

There is provided, in accordance with an embodiment, a dental guidanceassembly, comprising a rigid body comprising one or more tooth-shapedrecesses and a coupling structure. The dental guidance assemblycomprises at least two dental bur guides. Each dental bur guide isstructured to securely and removably couple to the coupling structure.Each dental bur guide comprises an elongated slot having the followingmeasurements of a length of 4 to 40 millimeters, a width of 1 to 4millimeters, and a depth of 2 to 10 millimeters. The elongated slotextends along a portion of a circumference of a treated tooth. Theelongated slots of the at least two dental bur guides have complementarystructures, such that, together, the elongated slots are configured tofacilitate a limitation of the motion of a dental bur to an entirety ofthe circumference of a treated tooth, and a depth suitable to form ashoulder on the treated tooth, for receiving a dental restoration.

In some embodiments, the coupling structure is ridge-shaped, where theridge surrounds a void for treating a tooth in the rigid body, and wherethe ridge is on a side of the rigid body opposing the side comprisingthe tooth-shaped recesses.

In some embodiments, the motion of the dental bur is limited by thecoupling structure and a central portion of each dental bur guide.

In some embodiments, each dental bur guide is comprised of a secondcoupling structure configured to securely and removably couple to thecoupling structure, a central structure. and a mechanical elementconnecting between the second coupling structure and the centralstructure and the elongated slot.

In some embodiments, the elongated slot is formed between the couplingstructure and the central structure, wherein the coupling structure isconfigured as a ridge-shaped structure, wherein the ridge surrounds avoid for treating a tooth in the rigid body, and wherein the ridge is ona side of the rigid body opposing the side comprising the tooth-shapedrecesses.

In some embodiments, the elongated slot is formed between the secondcoupling structure and the central structure, wherein the secondcoupling structure is configured as a ridge-shaped structure, whereinthe ridge surrounds a void for treating a tooth in the rigid body, andwherein the ridge is on a side of the rigid body opposing the sidecomprising the tooth-shaped recesses.

In some embodiments, the dental guidance assembly further comprises aliner. The liner comprises a sleeve configured to fit snuggly in theelongated slot and through which the dental bur is operated. The linercomprises an annular protruding ring surrounding one end of the sleevethat has an outer diameter larger than the elongated slot by at least0.5 millimeters.

In some embodiments, the tooth-shaped recesses and the couplingstructure are each located on different sides of the rigid body.

In some embodiments, the limitation is in a location, a height, and anangle of the dental bur.

In some embodiments, the dental guidance assembly further comprises asurface reshaping guide comprising a motion limiting structure forlimiting the motion of a dental bur when performing an occlusal surfacereshaping procedure.

There is provided, in accordance with an embodiment, a dental guidanceassembly comprising a rigid body having one or more tooth-shapedrecesses and a ridge. The dental guidance assembly comprises a dentalbur anchor comprising a dental bur sleeve, an opposing mechanicalelement, and a connecting arm between the dental bur sleeve and theopposing mechanical element, thereby forming a ridge anchoring structureconfigured to snugly glide along the ridge. the ridge is structured tocompletely surround a treated tooth, and is of a height, shape, andposition configured to limit a motion of a dental bur to form a shoulderaround the complete circumference of the treated tooth for receiving adental restoration when the dental bur is inserted into the dental bursleeve and the dental bur anchor is glided along the ridge.

In some embodiments, the dental bur anchor is incorporated into a dentaldrill.

In some embodiments, the dental bur is incorporated into the dental buranchor.

In some embodiments, the tooth-shaped recesses and the ridge are eachlocated on opposing sides of the rigid body.

In some embodiments, the motion of the dental bur is limited in alocation, a height, and an angle of the dental bur.

In some embodiments, the dental guidance assembly further comprises asurface reshaping guide comprising a motion limiting structure forlimiting the motion of a dental bur when performing an occlusal surfacereshaping procedure.

There is provided, in accordance with an embodiment, a computer programproduct for fabricating a dental guidance assembly. The computer programproduct comprises a non-transitory computer readable storage mediumhaving encoded thereon computer instructions to instruct one or morecomputer hardware processors to perform steps. The steps comprisereceiving a three-dimensional (3D) scan of teeth of a patient. The stepscomprise calculating a computerized teeth model of the teeth of thepatient. The steps comprise calculating a computerized assembly model ofa dental guidance assembly having the structure of a rigid bodycomprising one or more tooth-shaped recesses and a coupling structure.The dental guidance assembly has the structure of at least two dentalbur guides. Each dental bur guide is structured to securely andremovably couple to the coupling structure. Each dental bur guidescomprises an elongated slot having the measurements of a length of 4 to40 millimeters, a width of 1 to 4 millimeters, and a depth of 2 to 10millimeters. The elongated slot extends along a portion of acircumference of a treated tooth. The elongated slots of the at leasttwo dental bur guides have complementary structures, such that,together, the elongated slots are configured to facilitate a limitationof the motion of a dental bur. The dental bur is limited to an entiretyof the circumference of a treated tooth. The dental bur is limited to adepth suitable to form a shoulder on the treated tooth, for receiving adental restoration. The recesses are based on respective teeth of thecomputerized teeth model. The steps comprise preparing a set of 3Dfabricator instructions for fabricating the computerized assembly model.The steps comprise sending the set of 3D fabrication instructions to a3D fabricator, thereby fabricating the dental guidance assembly.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of receiving a userinput indicating the treated tooth.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of presenting thecomputerized teeth model on a user interface connected to the computerhardware processor(s).

In some embodiments, the 3D fabricator is a 3D computerized printer or a3D computerized milling device.

In some embodiments, the coupling structure is ridge-shaped, wherein theridge surrounds a void for treating a tooth in the rigid body, andwherein the ridge is on a side of the rigid body opposing the sidecomprising the tooth-shaped recesses.

In some embodiments, the motion of the dental bur is limited by thecoupling structure and a central portion of each dental bur guide.

In some embodiments, each dental bur guide comprises a second couplingstructure configured to securely and removably couple to the couplingstructure. Each dental bur guide comprises a central structure. Eachdental bur guide comprises a mechanical element connecting between thesecond coupling structure and the central structure. Each dental burguide comprises an elongated slot.

In some embodiments, the elongated slot is formed between the couplingstructure and the central structure, wherein the coupling structure isconfigured as a ridge-shaped structure, wherein the ridge surrounds avoid for treating a tooth in the rigid body, and wherein the ridge is ona side of the rigid body opposing the side comprising the tooth-shapedrecesses.

In some embodiments, the elongated slot is formed between the secondcoupling structure and the central structure, wherein the secondcoupling structure is configured as a ridge-shaped structure, whereinthe ridge surrounds a void for treating a tooth in the rigid body, andwherein the ridge is on a side of the rigid body opposing the sidecomprising the tooth-shaped recesses.

In some embodiments, computer program product further comprises a liner.The liner comprises a sleeve configured to fit snuggly in the elongatedslot and through which the dental bur is operated. The liner comprisesan annular protruding ring surrounding one end of the sleeve that has anouter diameter larger than the elongated slot by at least 0.5millimeters.

In some embodiments, the tooth-shaped recesses and the couplingstructure are each located on different sides of the rigid body. In someembodiments, the limitation is in a location, a height, and an angle ofthe dental bur.

In some embodiments, the computer program product further comprises asurface reshaping guide comprising a motion limiting structure forlimiting the motion of a dental bur when performing an occlusal surfacereshaping procedure. There is provided, in accordance with anembodiment, a computerized system for fabricating a dental guidanceassembly. The computerized system comprises hardware processor(s). Thecomputerized system comprises a 3D fabricator digitally connected to thehardware processor(s). The computerized system comprises anon-transitory computer readable storage medium having encoded thereoncomputer instructions to instruct the computer hardware processor(s) toperform the automatic steps. The steps comprise receiving athree-dimensional (3D) scan of teeth of a patient. The steps comprisecalculating a computerized teeth model of the teeth of the patient. Thesteps comprise calculating a computerized assembly model of a dentalguidance assembly. The dental guidance assembly has the structure of arigid body comprising one or more tooth-shaped recesses and a couplingstructure. The dental guidance assembly has at least two dental burguides that are each structured to securely and removably couple to thecoupling structure. Each dental bur guide comprises an elongated slot.The elongated slot has the measurements of a length of 4 to 40millimeters, a width of 1 to 4 millimeters, and a depth of 2 to 10millimeters. The elongated slot extends along a portion of acircumference of a treated tooth. The elongated slots of the at leasttwo dental bur guides have complementary structures, such that,together, the elongated slots are configured to facilitate a limitationof the motion of a dental bur. The dental bur is limited to an entiretyof the circumference of a treated tooth. The dental bur is limited to adepth suitable to form a shoulder on the treated tooth, for receiving adental restoration. The recesses are based on respective teeth of thecomputerized teeth model. The steps comprise preparing a set of 3Dfabricator instructions for fabricating the computerized assembly model.The steps comprise sending the set of 3D fabricator instructions to the3D fabricator, thereby fabricating the dental guidance assembly.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of receiving a userinput indicating the treated tooth.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of presenting thecomputerized teeth model on a user interface connected to the computerhardware processor(s).

In some embodiments, the 3D fabricator is a 3D computerized printer or a3D computerized milling device.

In some embodiments, the coupling structure is ridge-shaped, wherein theridge surrounds a void for treating a tooth in the rigid body, andwherein the ridge is on a side of the rigid body opposing the sidecomprising the tooth-shaped recesses.

In some embodiments, the motion of the dental bur is limited by thecoupling structure and a central portion of each dental bur guide.

In some embodiments, each dental bur guide comprises a second couplingstructure configured to securely and removably couple to the couplingstructure. Each dental bur guide comprises a central structure and amechanical element connecting between the second coupling structure andthe central structure. Each dental bur guide comprises the elongatedslot.

In some embodiments, the elongated slot is formed between the couplingstructure and the central structure, wherein the coupling structure isconfigured as a ridge-shaped structure, wherein the ridge surrounds avoid for treating a tooth in the rigid body, and wherein the ridge is ona side of the rigid body opposing the side comprising the tooth-shapedrecesses.

In some embodiments, the elongated slot is formed between the secondcoupling structure and the central structure, wherein the secondcoupling structure is configured as a ridge-shaped structure, whereinthe ridge surrounds a void for treating a tooth in the rigid body, andwherein the ridge is on a side of the rigid body opposing the sidecomprising the tooth-shaped recesses.

In some embodiments, the computer program product further comprises aliner. The liner comprises a sleeve configured to fit snuggly in theelongated slot and through which the dental bur is operated. The linercomprises an annular protruding ring surrounding one end of the sleevethat has an outer diameter larger than the elongated slot by at least0.5 millimeters.

In some embodiments, the tooth-shaped recesses and the couplingstructure are each located on different sides of the rigid body.

In some embodiments, the limitation is in a location, a height, and anangle of the dental bur. In some embodiments, the computer programproduct further comprises a surface reshaping guide comprising a motionlimiting structure for limiting the motion of a dental bur whenperforming an occlusal surface reshaping procedure.

There is provided, in accordance with an embodiment, a computer programproduct for fabricating a dental guidance assembly. The computer programproduct comprises a non-transitory computer readable storage mediumhaving encoded thereon computer instructions to instruct computerhardware processor(s) to perform automatic steps. The steps comprisereceiving a three-dimensional (3D) scan of teeth of a patient. The stepscomprise calculating a computerized teeth model of the teeth of thepatient. The steps comprise calculating a computerized assembly model ofa dental guidance assembly having the structure of a rigid body havingone or more tooth-shaped recesses and a ridge. The structure has adental bur anchor comprising a dental bur sleeve, an opposing mechanicalelement, and a connecting arm between the dental bur sleeve and theopposing mechanical element, thereby forming a ridge anchoring structureconfigured to snugly glide along the ridge. The ridge is structured tocompletely surround a treated tooth. The ridge is of a height, shape,and position configured to limit a motion of a dental bur to form ashoulder around the complete circumference of the treated tooth forreceiving a dental restoration when the dental bur is inserted into thedental bur sleeve and the dental bur anchor is glided along the ridge.The recesses are based on respective teeth of the computerized teethmodel. The steps comprise preparing a set of 3D fabricator instructionsfor fabricating the computerized assembly model. The steps comprisesending the set of 3D fabricator instructions to a 3D fabricator,thereby fabricating the dental guidance assembly.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of receiving a userinput indicating the treated tooth.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of presenting thecomputerized teeth model on a user interface connected to the computerhardware processor(s).

In some embodiments, the 3D fabricator is a 3D computerized printer or a3D computerized milling device.

In some embodiments, the dental bur anchor is incorporated into a dentaldrill.

In some embodiments, the dental bur is incorporated into the dental buranchor.

In some embodiments, the tooth-shaped recesses and the ridge are eachlocated on opposing sides of the rigid body.

In some embodiments, the motion of the dental bur is limited in alocation, a height, and an angle of the dental bur.

In some embodiments, the computer program product further comprises asurface reshaping guide comprising a motion limiting structure forlimiting the motion of a dental bur when performing an occlusal surfacereshaping procedure.

There is provided, in accordance with an embodiment, a computerizedsystem for fabricating a dental guidance assembly. The computerizedsystem comprises hardware processor(s). The computerized systemcomprises a 3D fabricator digitally connected to the hardwareprocessor(s). The computerized system comprises a non-transitorycomputer readable storage medium having encoded thereon computerinstructions to instruct the computer hardware processor(s) to performsteps. The steps comprise receiving a three-dimensional (3D) scan ofteeth of a patient. The steps comprise calculating a computerized teethmodel of the teeth of the patient. The steps comprise calculating acomputerized assembly model of a dental guidance assembly. The dentalguidance assembly has the structure of a rigid body having one or moretooth-shaped recesses and a ridge. The dental guidance assembly has adental bur anchor comprising a dental bur sleeve, an opposing mechanicalelement, and a connecting arm between the dental bur sleeve and theopposing mechanical element, thereby forming a ridge anchoring structureconfigured to snugly glide along the ridge. The ridge is structured tocompletely surround a treated tooth, and is of a height, shape, andposition configured to limit a motion of a dental bur to form a shoulderaround the complete circumference of the treated tooth for receiving adental restoration when the dental bur is inserted into the dental bursleeve and the dental bur anchor is glided along the ridge. The recessesare based on respective teeth of the computerized teeth model. The stepscomprise preparing a set of 3D fabricator instructions for fabricatingthe computerized assembly model. The steps comprise sending the set of3D fabricator instructions to the 3D fabricator, thereby fabricating thedental guidance assembly.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of receiving a userinput indicating the treated tooth.

In some embodiments, the computer instructions instruct the computerhardware processor(s) to perform the further step of presenting thecomputerized teeth model on a user interface connected to the computerhardware processor(s).

In some embodiments, the 3D fabricator is a 3D computerized printer or a3D computerized milling device.

In some embodiments, the dental bur anchor is incorporated into a dentaldrill.

In some embodiments, the dental bur is incorporated into the dental buranchor.

In some embodiments, the tooth-shaped recesses and the ridge are eachlocated on opposing sides of the rigid body.

In some embodiments, the motion of the dental bur is limited in alocation, a height, and an angle of the dental bur.

In some embodiments, the computerized system further comprises a surfacereshaping guide comprising a motion limiting structure for limiting themotion of a dental bur when performing an occlusal surface reshapingprocedure.

In addition to the exemplary aspects and embodiments described above,further aspects and embodiments will become apparent by reference to thefigures and by study of the following detailed description.

BRIEF DESCRIPTION OF THE FIGURES

Exemplary embodiments are illustrated in referenced figures. Dimensionsof components and features shown in the figures are generally chosen forconvenience and clarity of presentation and are not necessarily shown toscale. The figures are listed below.

FIG. 1 shows a schematic illustration of an isometric view from the toolside of a dental guiding assembly for treating a tooth;

FIG. 2 shows a schematic illustration of an isometric view from thetooth side of a rigid body;

FIG. 3 shows a schematic illustration of an isometric view from the toolside of a rigid body;

FIG. 4 shows a schematic illustration of a cross section view of adental guiding assembly;

FIG. 5 shows a schematic illustration of complementary guiding parts;

FIG. 6 shows a schematic illustration of a dental bur sleeve;

FIG. 7 shows a schematic illustration of an isometric view from the toolside of a dental guide assembly;

FIG. 8 shows a schematic illustration of a dental bur anchoringstructure;

FIG. 9 shows a schematic illustration of a dental bur anchoringstructure with a dental bur;

FIG. 10 shows a schematic illustration of a second dental guidingassembly during a tooth treatment;

FIG. 11A shows a schematic illustration of an attachment to a dentalguiding assembly for occlusal tooth resurfacing;

FIG. 11B shows a schematic illustration of an exploded view of anattachment to a dental guiding assembly for occlusal tooth resurfacing;and

FIG. 12 shows a flowchart of a method to treat a tooth with a dentalguiding assembly.

DETAILED DESCRIPTION

Disclosed herein are assemblies, computer program products, methods, andsystems for use in guiding a dental tool when performing a toothreshaping procedure. A planned three-dimensional (3D) tooth reshapingmay be performed with a dedicated guide assembly comprising severalparts. A rigid body part comprises one or more recesses on one side ofthe rigid body to mate and/or attach with one or more non-treated teethof the subject. The rigid body comprises a gap around the treated tooth,and a coupling structure, such as a protruding ridge, near and/orsurrounding the gap on the opposite side from the recesses. Anotheroptional part may be a dental tool sleeve that provides a low frictionchannel for the dental bur operation. A further optional part may be ananchoring structure for limiting the motion of the sleeve, such as toallow gliding along the protruding ridge.

The planned tooth treatment may be determined by a dental surgeon, uponreviewing the status of a patient's teeth. For example, a dental surgeonreceives a 3D scan of a patient's teeth, and selects one or more of theteeth for a dental restoration procedure. As embodied herein, one ormore hardware processors, such as a computer with dedicated software,may automatically receive the 3D scan and the dental surgeon'sselections, and automatically calculate a 3D tooth model, and areshaping plan for the selected teeth. The dental surgeon may review thereshaping plans, and optionally modify them as needed. The hardwareprocessor(s) may automatically selects the dental guide assemblyembodiment that most efficiently performs the reshaping, such as withthe least amount of time, the least amount of material, the least amountof tooth reshaping, the least expenses, and/or the like. Optionally, thedental surgeon may review hardware processor calculations and/orselections at any time, and optionally modify them as needed.

The hardware processor(s) may automatically model the parts of theassembly, and calculate the 3D fabrication instructions that willproduce the assembly. The hardware processor(s) may automatically send3D fabrication instructions to a 3D computerized fabrication deviceconnected to the hardware processor, and once the assembly has beenfabricated the dental surgeon may perform the planned toothreshaping(s). Since the tooth reshaping is known, the dentalrestorations may also be fabricated similarly to and optionally at thesame time as the assembly.

In one embodiment, the anchoring structure may be an annular ringprotrusion around one end of the sleeve, and the coupling structure usedto attach two or more dental bur guides that contain a slot to guide thesleeve along a planned location, height, and angle. In this embodiment,the sleeve protrusion limits the position of the dental bur, and eachslot of the dental bur guides guide the sleeve along at least part ofthe circumference of the tooth. Thus the position of the dental bur maybe limited as it moves around the circumference of the treated tooth andreshapes tooth surface. In this embodiment, the slots of the dental burguides are complementary in that each slot allows covering some of thetreated tooth circumference and by switching between the dental burguides the complete circumference of the tooth may be reshaped.

Reference is now made to FIG. 1, which is a schematic illustration of anisometric view from the tool side of a dental guiding assembly 100 fortreating a tooth. As used herein, the phrase “tooth side” refers to aside of a part or assembly closer to a tooth, and the phrase “tool side”refers to the side of a part or assembly closer to a dental tool. Dentalguiding assembly 100 comprises a rigid body 102 which may be coupled toa dental bur guide 104 near a tooth 120 to be treated.

Rigid body 102 may be fabricated using digital 3D printing technologies,3D computerized milling technologies, and/or the like. For example,rigid body 102 is manufactured with a desktop 3D printer in the dentalsurgeon's office. Rigid body may be fabricated from a biocompatiblematerial, a plastic, a metal, a ceramic, a temporary material, apermanent material, a composite material, such as a combined resin andmetal material, a reusable material, a recyclable material, a disposablematerial, and/or the like. For example, rigid body is fabricated fromnylon (polyamide), acrylic, acrylonitrile butadiene styrene (ABS),polyetherimide, brass, alumide, carbon fiber, resin, paper, rubber,Cross-linked polyethylene (PEX, XLPE), ethylene vinyl acetate (EVA),poly(methyl methacrylate) (PMMA), polyacrylic acid (PAA), Polybutylene(PB), polybutylene terephthalate (PBT), polycarbonate (PC),polyetheretherketone (PEEK), polyester (PEs), polyethylene (PE),polyethylene terephthalate (PET, PETE), polyimide (PI), polylactic acid(PLA), polyoxymethylene (POM), polyphenyl ether (PPE), polypropylene(PP), polystyrene (PS), polysulfone (PES), polytetrafluoroethylene

(PTFE), polyurethane (PU), polyvinyl chloride (PVC), polyvinylidenechloride (PVDC), styrene maleic anhydride (SMA), styrene-acrylonitrile(SAN), and/or the like.

Optionally, one part of a dental guide assembly is fabricated from onetype of material and a second part from a second type of material.Optionally, a single part is partially fabricated from a first materialand partially from a second material.

Dental bur guide 104 may have an elongated slot 108 which covers part ofa circumference of treated tooth 120. Elongated slot 108 may be formedbetween a central portion 106 and rigid body 102 coupling structure.Alternatively, elongated slot 108 may be formed between a centralportion 106 and dental bur guide 104 (this configuration is not shown).Assembly 100 may include a dental bur sleeve 110, through which a dentalbur 130 may be operated to reshape the treated tooth 120.

Elongated slot 108 of dental bur guide 104 may have a length of 4 to 40millimeters along the circumference of a treated tooth, a slot width of1 to 4 millimeters, and a slot depth of 2 to 10 millimeters. As usedherein, the orientations of the assembly are based on the patientorientations when the assembly is attached to a patient. The width ofelongated slot 108 is the smallest dimension of elongated slot 108 on anaxial plane. The length of elongated slot 108 is the length of a curvefollowing elongated slot 108 in an axial plane. The depth of elongatedslot 108 is the dimensions of elongated slot 108 in the inferiorsuperior direction.

For example, elongated slot 108 has a length of 25 millimeters, a widthof 2 millimeters, and a depth of 5 millimeters. Two such elongated slotsof dental bur guides 104 of the same length may be needed to completelyreshape a 40 millimeter tooth circumference, such that there are 2.5millimeter overlaps at each end of the elongated slots between twocomplementary dental bur guides. Three such elongated slots of dentalbur guides of the same length may be needed to completely reshape a 60millimeter tooth circumference, such that there are 2.5 millimeteroverlaps at each end of the elongated slots between two complementarydental bur guides 104. Optionally, each dental bur guide 104 and/orelongated slot 108 limits the dental bur to a different height so thatany reshaping of a treated tooth is achievable.

Reference is now made to FIG. 2, which is a schematic illustration of anisometric view from the tooth side of a rigid body 102. Rigid body 102contains one or more tooth-shaped recesses 206A and 206B, such asimpressions of teeth, from a 3D tooth model for a particular patient. Avoid 210 may be left when fabricating rigid body 102, such as a gap inrigid body 102, for dental bur access to a treated tooth. A couplingstructure 208 may be located around the void 210 for attaching a dentalbur guide. Edge 204 may be the anterior edge of rigid body 102,positioned towards a patient's incisor teeth during treatment.

Reference is now made to FIG. 3, which is a schematic illustration of anisometric view from the tool side of a rigid body 300. Rigid body 300comprises a coupling structure 208 which may have a variable height withrespect to tool side 304.

Reference is now made to FIG. 4, which is a schematic illustration of across section view of a dental guiding assembly 400. A rigid body of theassembly has recesses for attachment to a patient's teeth 422, and avoid surrounding a treated tooth 420. A coupling structure 208 securelyand removeably attaches a dental bur guide 406 to the rigid body. Dentalbur guide 406 facilitates the generation of an elongated slot throughwhich a sleeve 110 may be introduced for guiding a dental bur 130 aroundat least part of the circumference of treated tooth 120.

Reference is now made to FIG. 5, which is a schematic illustration ofcomplementary dental bur guides (500A and 500B). One or morecomplementary dental bur guides 500A and 500B may be secured by africtional fit to coupling structure, such as 208 of FIG. 3. Forexample, an outer wall coupling structure 506A may have a shorter heightthan protruding coupling structure 208 of FIG. 3.

A retaining mechanical element 508A, which may be semi-elliptical, mayextend from outer wall coupling structure 506A to an inner guidingstructure 504A. An elongated slot 502A may be created between innerguiding structure 504A and protruding coupling structure 208 of FIG. 3to limit the motion therewithin of the dental bur. Complementary dentalbur guide 500B may be configured in a similar manner to dental bur guide500A to define a complementary elongated slot 502B, such that thespatial union of the two elongated slots 502A and 502B cover thecomplete circumference of the treated tooth.

Reference is now made to FIG. 6, which is a schematic illustration of adental bur sleeve 110. Dental bur sleeve 110 comprises a hollow sleeveportion 602, which when inserted into an elongated slot, may beconfigured to guide a dental bur around at least part of thecircumference of a treated tooth. An annular retaining ring 604 at oneend of the sleeve 110 prevents the sleeve 110 from being displacedtowards the treated tooth. The hollow void 606A and 606B of the sleeve110, may be configured to accept the shaft of a dental bur, such as around orifice within which the dental bur rotates. An outer surface ofhollow sleeve portion 602 may have a round, rectangular, trapezoid,and/or the like shape to allow smooth gliding motion along an elongatedslot, and may have rounded corners to facilitate the gliding.

The length of sleeve 110 may be between 3 and 20 millimeters, hollowsleeve portion 602 may have an outer diameter of between 1 and 4millimeters and an inner diameter of between 0.5 and 2.8 millimeters.Annular retaining ring 604 may have an outer diameter of between 1.5 and6 millimeters and be between 0.5 to 2 millimeters in length along theaxis of sleeve 110. For example, length of sleeve 110 may be 7millimeters, hollow sleeve portion 602 may have an outer diameter of 2millimeters, hollow sleeve portion 602 may have an inner diameter of 1.6millimeters, annular retaining ring 604 may have an outer diameter of 3millimeters, and annular retaining ring 604 may be 1.2 millimeters inlength with a radius of curvature of 0.5 millimeters.

At times, during the course of a reshaping operation, the treated toothmay have a decayed portion which may be removed in order to ensure thatthe tooth structure supports the dental restoration to be connectedthereto and to prevent spreading of infection. The assembly may beremoved to allow access to the treated tooth for the removal of thedecayed portion. Following removal of the decayed portion, restorativematerial such as amalgam and/or resin may be added. The assembly may bereattached to the subject, and a dental bur may be again activated alongthe guide(s) so that a reshaping operation may remove remnants of therestorative material or any other undesirable material. Aftercompletion, the configuration of the treated tooth reshaped structuremay conform to the planned reshaped tooth structure. Optionally, a firstguide may be used to remove a decayed portion of the tooth, a fillingmaterial used to build up the tooth, and a second, different guide usedto reshape the tooth and filling material to the desired shape.

The dental guide assemblies described herein solve problems ofrepeatable and accurately guiding a dental tool, such as a dental bur,along a path for reshaping a treated tooth by the dental professional. Achange in angular disposition of the dental tool may be exacerbated whenthe dental professional may be fatigued or stressed, leading toincompatibility between the reshaped tooth structure and the dentalrestoration and necessitating a modified dental restoration to beformed, thus increasing treatment time, user effort, patient discomfort,treatment cost, and/or the like.

The benefits of using a guiding assembly in dental restorationprocedures may be that the angular disposition of the dental tool withrespect to the tooth structure is consistently maintained. For example,by selecting the appropriate dental bur and appropriate ridgeorientation, the angle of the reshaped tooth taper can be controlledaccurately. For example, a tapering angle of a reshaped tooth is between0 and 12 degrees, such as 2 degrees, 3 degrees, 4, degrees, 5, degrees,6 degrees, 8 degrees, 10 degrees, and the like. A further benefit of aguiding assembly used in dental restoration procedures may be that thedepth of the dental tool within the tooth structure is controlled and/ormaintained. A further benefit of a guiding assembly may be to provide avisible delimitation of the preparation and/or restoration site.

In another embodiment, the dental guide assembly may comprise a rigidbody with a ridge structure, and a dental bur anchoring element forgliding along the ridge and limiting the motion of a dental bur to aplanned location, height, and angle. The dental bur anchoring elementmay comprise a dental bur sleeve, an arm, and an anchoring mechanicalelement opposing the sleeve, where the arm connects between the sleeveand opposing element. In this embodiment, the sleeve, arm, and anchoringmechanical element saddle the ridge and guide the position of the dentalbur as it moves around the circumference of the treated tooth andreshapes a tooth surface. For example, the sleeve, arm and anchoringmechanical element form three contact points to saddle three pointsalong a cross section of the ridge, and thus the anchoring elementglides along the ridge as the dental bur reshapes the circumference ofthe treated tooth.

Reference is now made to FIG. 7, which is a schematic illustration of anisometric view from the tool side 708 of a dental guide assembly 700.Dental guide assembly 700 comprises a ridge 704 for guiding a dental bursleeve 702 with anchoring element along a lip 706 of the ridge. Lip 706limits the motion of a dental bur 720 as it glides along the ridge 704around the circumference of the tooth and reaches the tooth to match adental restoration, and/or the like. For example, a molar tooth isreshaped, but dental guide assembly 700 may be selected so as tosurround any tooth needed to be reshaped.

Optionally, the coupling structure may be configured to surround only aportion of the treated tooth, for example the buccal surface of thetreated tooth to which a veneer is desired to be attached. As usedherein, “longitudinal” is in a direction similar to, but not identicalto, the length of the dental arch between a first distal tooth to asecond distal tooth. “buccal” is in a direction towards the cheeks while“lingual” is in a direction towards the tongue.

Reference is now made to FIG. 8, which is a schematic illustration of adental bur anchoring structure 702. Dental bur anchoring structure 702comprises a sleeve part 808 for holding the shaft of a dental bur, anopposing anchoring mechanical element 802 for contacting the opposingside of the ridge from sleeve 808, and an arm 804 to rigidly connectbetween sleeve 808 and opposing element 802. For example, the ridge mayhave a constant cross sectional thickness. In this example, sleeve 808and opposing element 802 may have outer cylindrical shaped surfaces toform two parallel lines of contact at a distance G 812 between anchoringstructure 702 and the ridge. The spacing G 812 may be substantiallyequal to, or slightly greater than, the ridge. The third point ofcontact may be a side 810 of arm 804 closest to the ridge.

Alternatively, the two lines of contact are not parallel or nearparallel to allow easy attachment of anchoring structure 702 to theridge. Alternatively, sleeve 808 and opposing element 802 may have aflat surface on the sides facing the ridge to allow a contact surfacewith the ridge instead of a contact line. Sleeve 808 and opposingelement 802 length may be shorter than the height of the ridge. Sleeve808 comprises a round aperture 806 for receiving the dental bur shaft.

Optionally, the ridge is inclined with respect to the inferior superiordirection, for example defining an angle therebetween of up to 6degrees.

Alternatively, the ridge may comprise a bead along the lip of the ridge,and a corresponding void between sleeve 808 and opposing element 802 tolimit the motion of the dental bur. In this alternative example, thebead along the ridge may have one section of the ridge without the beadfor attachment of anchoring structure 702 to the ridge. Alternatively,the angular limitation may be maintained by means of a tongue and groovearrangement, where one of the tongue or groove is on the lip of theridge, and the other of the tongue or groove is on the ridge contactingsurface of anchoring structure 702. For example, a protrusion extendsalong the ridge at a constant cross sectional shape and anchoringstructure 702 has a matching groove to receive the protrusion. When theprotrusion is introduced into the matching groove, the side edges of thegroove may have a minimal clearance to the protrusion to enablelongitudinal displacement of the holder, yet set the holder in a fixedangular relation with respect to the tooth structure. Reference is nowmade to FIG. 9, which is a schematic illustration of a dental buranchoring structure 702 with a dental bur 720 and 922. This illustrationshows the relation of the sleeve 808, arm 802 and the dental bur 922.

Reference is now made to FIG. 10, which is a schematic illustration of asecond dental guiding assembly during a tooth treatment. The assemblycomprises a rigid body 922 with one or more tooth shaped recesses forattaching to one or more non-treated teeth 120. As an anchoringstructure 702 glides along a ridge surrounding a treated tooth, a dentalbur 922 reshapes the surface of a tooth for receiving a dentalrestoration.

In operation, the rigid body may be removeably attached to one or moreteeth. The anchoring element may be attached with the dental bur to adental drill, and may be placed in contact with the ridge, such that thedental drill may glide along the ridge while the attached dental burreshapes the treated tooth. A dental professional may operate the dentaltool to reshape a treated tooth

Optionally, dental bur guide and/or rigid body comprise one or moredrill guide holes for using a dental bur to drill a hole in the treatedtooth. Optionally, an anchoring structure comprises an extended sleeveto better hold the dental bur shaft.

Optionally, an occlusal bur guide is used to resurface the occlusal faceof a treated tooth when inserted into a coupling structure, ridge,and/or the like, such as 208 in FIG. 2. For example, a disk shaped guidecomprises a disk body, a central orifice for retaining a dental bur, anda lateral motion limiting structure on the side of the disk facing thetooth is inside the void of the rigid base around the treated tooth. Thedental bur is operated on a tooth inside the void of the rigid basearound the treated tooth. The lateral motion limiting structure limitsthe motion of the dental bur on the axial plane when the structure meetsthe ridge, coupling structure, and/or the like. The inferior-superiormotion of the dental bur is limited by the disk meeting the ridge, andthus the reshaping of the tooth on the occlusal surface is limited tothe structure of the occlusal bur guide and the ridge, couplingstructure, and/or the like.

Optionally, an occlusal base is used with the occlusal bur guide toallow the occlusal resurfacing of a tooth. For example, an occlusal baseis attached to the coupling structure, ridge, and/or the like, to limitthe motion of an occlusal bur guide when the coupling structure, ridge,and/or the like are not configured for this. For example, two dental burguides and a sleeve are used to reshape the margins of the tooth, and anocclusal base and occlusal bur guide are used to reshape the occlusalsurface of the tooth. This allows producing a single rigid base for evencomplex reshaping procedures, by producing smaller fitted guides thatcouple with the rigid base.

For example, a single rigid base comprising ridge structure and a sleevemay be used for the circumferential reshaping of a tooth and an occlusalbur guide used for occlusal reshaping. For example, a single rigid basecomprising a ridge structure and a sleeve may be used for thecircumferential reshaping of a tooth and an occlusal base and bur guideused for occlusal reshaping. For example, a single rigid base comprisinga ridge structure, two dental bur guides, and a sleeve may be used forthe circumferential reshaping of a tooth and an occlusal base and burguide used for occlusal reshaping.

Optionally, an occlusal guiding assembly is used to reshape an occlusalsurface of a tooth. Reference is now made to FIG. 11A, which is aschematic illustration of an attachment 1100 to a dental guidingassembly for occlusal tooth resurfacing. An occlusal guiding assemblyattachment 1100 may comprise an occlusal base 1106 for attachment to acoupling structure of a rigid base, a ridge structure, and/or the like.Attached to base 1106 may be an arm 1104 with a pin 1112 to allowstability of the dental bur during operation. An occlusal bur guide 1116of attachment 1100 may comprise an arm 1114 with a slot 1110 matchingpin 1112. An orifice 1102 in occlusal bur guide 1116 may receive theshaft of a dental bur 1120. During operation of a dental drill, thedental surgeon may move occlusal bur guide 1116 over base 1106, but thedental bur may be limited by slot 1110, pin 1112, other matchingstructures between occlusal bur guide 1116 and base 1106, and/or thelike, so that the occlusal surface of a treated tooth may be reshapedand the dental bur is operated in a stable manner.

Reference is now made to FIG. 11B, which shows a schematic illustrationof an exploded view of an attachment to a dental guiding assembly forocclusal tooth resurfacing. An occlusal bur guide 1116 comprises alimiting structure 1136 surrounding the central orifice for insertion ofa dental bur through occlusal bur guide 1116. For example, when thedental bur is operated on a tooth, occlusal bur guide 1116 limits theinferior-superior motion of the dental bur for reshaping the occlusalsurface of the tooth by meeting the ridge structure which limits thedental bur from penetrating the tooth too deeply. An occlusal base 1106may be used to alter the limiting configuration of the ridge structure,both in the inferior-superior direction using the height of occlusalbase 1106, and in the axial plane using a central orifice 1126 inocclusal base 1106 that limits the lateral motion of limiting structure1136.

Optionally, part of the occlusal surface of the tooth is reshaped.

Optionally, elements 1110 and 1112 have alternative configurations tostabilize between elements 1116 and 1106 during operation.

Attachment 1100 may limit the height of the dental bur during operation.For example, the surface of moveable part 1116 and the matching surfaceof base 1106 are flat surfaces so the occlusal surface of a treatedtooth is reshaped in a corresponding flat surface. Attachment 1100 mayselectively limit the height of the dental bur during operation. Forexample, the surface of moveable part 1116 and the matching surface ofbase 1106 are curved surfaces so the occlusal surface of a treated toothis reshaped in a corresponding curved surface.

Optionally, a dental guide assembly is fabricated using a process, suchas a computer program product comprising processor instructions, ahardware system with processor instructions stored thereon, and/or thelike. Reference is now made to FIG. 12, which is a flowchart of a method1200 to treat a tooth with a dental guiding assembly. A hardwareprocessor may automatically receive a three-dimensional (3D) scan of theteeth, such as 3D mapping 1202 of the teeth, and automatically calculate1204 a teeth model from the scan. The 3D teeth model, such as a digitalimpression 3D model, may be used to automatically model 1206 a guideassembly and automatically model 1208 (optionally) one or more dentalrestorations, such as one or more prostheses, optionally with manualinput from a dental surgeon, such as an indication of the one or morecorresponding teeth to be treated.

For example, a 3D scan is performed by an iTero® 3D digital scanner fromAlign Technology, Inc. For example, a 3D scan is performed by aGALILEOS® 3-D diagnostic system from Sirona Dental Systems GmbH.

Optionally, the dental surgeon reviews 1210 the treatment plan beforeproducing the assemblies and/or dental restorations. Each assemblycomprises a rigid body and optionally two or more guiding structuresaccording to embodiments hereinabove. The rigid body comprises recessesto match one or more teeth of the 3D teeth model for attaching the rigidbody to a patient. To automatically produce 1212 the guide assembly,printing and/or fabricating instructions are automatically generated fora 3D printer and/or 3D fabricator to fabricate the rigid body and otherparts needed, and the printer and/or fabricator instructions are sent toa 3D printer and/or 3D fabricator attached to the hardware processor. Asused herein, the phrase 3D printer means a computerized printer thatreceives 3D printing instructions from a hardware processor and producesa fabricated 3D object from a suitable material. For example, a ZRapid®SLA200 Rapid 3D Printer is used to fabricate a dental guide assembly.For example, a ZRapid® SLS400 Rapid 3D Printer is used to fabricate adental guide assembly. For example, a ZRapid® SLM150 Metal 3D Printer isused to fabricate a dental guide assembly. For example, a Stratasys®Mojo® is used to fabricate a dental guide assembly. As used herein theterm fabricating and/or fabricator is used to mean a computerizedmethods and/or device for constructing a 3D model, assembly, part,structure, and/or the like.

Optionally, the dental restoration(s) are automatically produced 1214 bythe same or similar 3D fabricator using a suitable dental restorationmaterial. Optionally, the dental restoration(s) are automaticallyproduced 1214 by sending the corresponding 3D fabricator instructions toa manufacturing sub-contractor. Optionally, the one or more guideassemblies are automatically produced 1212 by sending the corresponding3D fabricator instructions to the same or a different a manufacturingsub-contractor. Optionally, the dental restoration is modelled to matchthe occlusal surface of the corresponding teeth according to the 3Dmodel.

During the treatment procedure, the rigid body may be attached 1216 tothe non-treated teeth to serve as a basis for a coupling structure beingvariably shaped in accordance with a preplanned tooth structurereshaping plan. A dental tool, such as a bur, drill bit, or the like,may be guided through the sleeve as the sleeve glides along the guide toshape 1218 a treated tooth using the assembly. Once the treated tooth isreshaped, a tooth may be treated 1220, such as by attaching a dentalrestoration, a dental prosthesis, a tooth surface, a tooth crown, and/orthe like.

Optionally, the length of a dental bur shaft and sleeve are selected tomatch the dental guide assembly. For example, a longer dental bur shaftmay be needed to reshape the tooth using a dental guide assembly.

Optionally, a dental prosthesis is also fabricated based on a 3D teethmodel. For example, a crown is fabricated to match the tooth reshapingperformed using the dental guiding assembly and a contralateral tooth,an opposing tooth, a standard 3D tooth model, and/or the like. Forexample, Sirona Cerec dental crown manufacturing machine is used to makea dental crown. For example, IOS Technologies Inc. TS150 dental crownmilling subsystem is used to make a dental crown.

A 3D mapping 1202 of a patient's teeth may be performed based on visiblesurfaces of a selected set of teeth including the treated toothstructure, for example by a digital camera or a blue laser insertedwithin the oral cavity. The captured images are automatically processedto calculate 1204 a 3D teeth model. Optionally, X-ray images of the sameselected set of teeth may be obtained and processed to produce 3D X-raydata that is representative of both visible surfaces and gum obscuredsurfaces of the treated tooth. The digital impression 3D model may beprocessed to identify treatable regions of the treated tooth, forexample in outline form. The 3D X-ray data may also be processed, ifneeded, to assist in calculating 1204 a 3D tooth model and/oridentifying the treatable regions. Optionally, 3D tooth models may becalculated 1204 from computed tomography images, ultrasound images,panoramic teeth images, dental x-ray images, and/or the like.

A virtual reshaped tooth structure, which may be representative of theconfiguration of the treated tooth following the reshaping operation,may be generated when taking into account the identified treatableregions and the capabilities of the selected dental bur. A virtualprosthetic dental restoration, which may be representative of an actualdental restoration, may be configured to match a reshaped tooth surface.

The 3D tooth model may be compared with the virtual reshaped toothstructure, and the peripheral wall of the guide surrounding the treatedtooth may be virtually generated to limit the operation of a dental bur.Thus the dental professional, when the dental bur is guided by theassembly, may be limited in manipulating the dental tool while itreshapes the treated tooth according to the treatment plan, such as toachieve the virtual reshaped tooth structure.

A digital model of a rigid body may be generated by using the digitalimpression 3D model to generate an accurate representation of toothreceiving recesses matching one or more teeth, a void area to access thetreated tooth, and a coupling structure surrounding the void area. Ifnecessary, the rigid body may be generated with two or more couplingstructures for treating two or more respective teeth.

The virtually generated rigid body may be rendered and displayed forreview by a dental professional, and optionally analyzed structurally tocheck the structural integrity of the reshaped tooth and/or the dentalrestoration. When the virtually generated rigid body needs to bemodified manually, the dental professional may interface with an inputdevice to input modifying data to a computerized device. After thevirtually generated rigid body is approved by the dental professional,the rigid body may be produced by a computerized machining unit forselectively removing material from a block of dentally compatiblematerial, such as polymeric material, in accordance with the virtuallygenerated rigid body.

When an assembly comprises two or more dental bur guides, the treatedtooth may be reshaped partially by each dental bur guide, and the dentalbur guides used one by one till the complete tooth is reshaped accordingto the treatment plan.

When the dental professional desires to operate the dental toolcontinuously, a ridge like structure may be used to surround the toothto guide an anchoring structure for reshaping the tooth.

The dental bur may be replaced with one having longer abrading surfaces,head, neck, shank, and/or the like. For example, when desired to connecta veneer to the anterior surface of a treated tooth. The dental bur maybe replaced with one having a longer shaft, shank, and/or the like. Theguiding ridge and/or slot may have different angular dispositions, tovary the reshaped surface as needed.

In the description and claims of the application, each of the words“comprise” “include” and “have”, and forms thereof, are not necessarilylimited to members in a list with which the words may be associated. Inaddition, where there are inconsistencies between this application andany document incorporated by reference, it is hereby intended that thepresent application controls.

What is claimed is:
 1. A computer program product for fabricating adental guidance assembly, comprising: a non-transitory computer readablestorage medium having encoded thereon computer instructions to instructat least one computer hardware processor to perform the steps of:receiving a three-dimensional (3D) scan of teeth of a patient;calculating a computerized teeth model of the teeth of the patient;calculating a computerized assembly model of a dental guidance assemblyhaving the structure of: a rigid body comprising at least onetooth-shaped recess and a coupling structure; and at least two dentalbur guides that are each: structured to securely and removably couple tosaid coupling structure, and comprising an elongated slot having thefollowing measurements:  a length of 4 to 40 millimeters, a width of 1to 4 millimeters, and a depth of 2 to 10 millimeters,  wherein theelongated slot extends along a portion of a circumference of a treatedtooth, wherein the elongated slots of said at least two dental burguides have complementary structures, such that, together, the elongatedslots are configured to facilitate a limitation of the motion of adental bur to: an entirety of the circumference of a treated tooth, anda depth suitable to form a shoulder on the treated tooth, for receivinga dental restoration, wherein the at least one recess is based onrespective at least one of the teeth of the computerized teeth model;preparing a set of 3D fabricator instructions for fabricating thecomputerized assembly model; and sending the set of 3D fabricationinstructions to a 3D fabricator, thereby fabricating the dental guidanceassembly.
 2. The computer program product of claim 1, wherein thecomputer instructions instruct the at least one computer hardwareprocessor to perform the further step of receiving a user inputindicating the treated tooth.
 3. The computer program product of claim1, wherein the computer instructions instruct the at least one computerhardware processor to perform the further step of presenting thecomputerized teeth model on a user interface connected to the at leastone computer hardware processor.
 4. The computer program product ofclaim 1, wherein the 3D fabricator is at least one of a 3D computerizedprinter and a 3D computerized milling device.
 5. The computer programproduct of claim 1, wherein the coupling structure is ridge-shaped,wherein the ridge surrounds a void for treating a tooth in the rigidbody, and wherein the ridge is on a side of the rigid body opposing theside comprising the tooth-shaped recesses.
 6. The computer programproduct of claim 1, wherein the motion of the dental bur is limited bythe coupling structure and a central portion of each dental bur guide.7. The computer program product of claim 1, wherein each dental burguide is comprised of: a second coupling structure configured tosecurely and removably couple to said coupling structure; a centralstructure; and a mechanical element connecting between the secondcoupling structure and the central structure; and the elongated slot. 8.The computer program product of claim 7, wherein the elongated slot isformed between the coupling structure and the central structure, whereinthe coupling structure is configured as a ridge-shaped structure,wherein the ridge surrounds a void for treating a tooth in the rigidbody, and wherein the ridge is on a side of the rigid body opposing theside comprising the tooth-shaped recesses.
 9. The computer programproduct of claim 7, wherein the elongated slot is formed between thesecond coupling structure and the central structure, wherein the secondcoupling structure is configured as a ridge-shaped structure, whereinthe ridge surrounds a void for treating a tooth in the rigid body, andwherein the ridge is on a side of the rigid body opposing the sidecomprising the tooth-shaped recesses.
 10. The computer program productof claim 1, further comprising a liner, the liner comprising: a sleeveconfigured to fit snuggly in the elongated slot and through which thedental bur is operated; and an annular protruding ring surrounding oneend of the sleeve that has an outer diameter larger than the elongatedslot by at least 0.5 millimeters.
 11. The computer program product ofclaim 1, wherein the at least one tooth-shaped recess and the couplingstructure are each located on different sides of the rigid body.
 12. Thecomputer program product of claim 1, wherein the limitation in alocation, a height, and an angle of the dental bur.
 13. The computerprogram product of claim 1, further comprising a surface reshaping guidecomprising a motion limiting structure for limiting the motion of adental bur when performing an occlusal surface reshaping procedure. 14.The computer program product of claim 1, wherein calculating acomputerized assembly model comprises calculating a model of a dentalguidance assembly having the structure of: a rigid body having at leastone tooth-shaped recess and a ridge; and a dental bur anchor comprising:a dental bur sleeve, an opposing mechanical element, and a connectingarm between the dental bur sleeve and the opposing mechanical element,thereby forming a ridge anchoring structure configured to snugly glidealong the ridge; wherein the ridge: is structured to completely surrounda treated tooth, and is of a height, shape, and position configured tolimit a motion of a dental bur to form a shoulder around the completecircumference of the treated tooth for receiving a dental restorationwhen the dental bur is inserted into the dental bur sleeve and thedental bur anchor is glided along the ridge.